Habit and habitat: Member of this phylum shows a great variety in structuralorganization, habit and habitat. Most of the members have shells. They are marines and some occur in hilly region and in forest or in plain land. Some species live in different types of fresh water, e.g. snail, octopus and bivalve.
a) Body is soft, generally covered by hard shell.
b) Muscular foot present on the ventral side of the body for locomotion.
c) Respiration by gills or lung.
Pila globosa(Apple snail)
Octopus vulgaris (Octopus)